The invention is directed to a water-cooled housing for a hot-blast slide valve particularly in conduits lined with refractory material, comprising annular coolant channels that are arranged at both sides of a guide space for a valve plate lying following one another in a flow direction of the hot-blast and that are seated concentrically inside one another in pairs as employed, for example, in blast heating systems, blast furnaces or high-temperature testing stands in testing institutes as well.
Such housings are known. Thus, DE-AS 23 64 915 discloses a water-cooled housing for hot-blast slide valves, whereby an annular coolant channel placed preceding the guide space in flow-through direction of the hot blast and an annular coolant channel placed following the guide space in flow-through direction of the hot blast are respectively connected immediately following one another in the same coolant circulation. Such a housing has definitely proven itself in practical operation; it is considered a disadvantage, however, that the manufacture of the housing which is usually executed as a welded structure is relatively complicated since a relatively great number of component parts must be manufactured for forming the annular coolant channels and these must then be joined to one another with a corresponding plurality of welds.
A water-cooled housing for hot-blast slide valves is also disclosed by DE-AS 23 28 085. This Reference discloses a water-cooled high-temperature slide valve, particularly a hot-blast slide weld, whereby annular channels for the coolant (water) are provided in the housing which proceed from the upper part of the slide valve along the sealing ledges at both circumferential sides down to the lower region of the housing and discharge into at least one cooling channel via overflow openings provided at this location, this cooling channel returning around the region of the housing arranged around the valve plate to the upper part of the housing in which the coolant discharge is located, whereby the flow cross-section of the cooling channel wherein the coolant is returned is smaller--at least in its lower region covering 180.degree.--but at most of the same size as the overall flow cross-section of the annular channels. The object of the inventor in that patent was to enhance the reliability and the efficiency of the cooling in high-temperature slide valves, particularly hot-blast slide valves, namely while making the housing design simpler and less expensive as well as reducing the space requirements of the housing design insofar as possible at the same time. This housing is also fabricated as a weldment and has a rather complicated structure since special baffles are provided in the coolant space in order to maintain a coolant speed that is adequate for entraining solids situated in the coolant, this increasing the outlay of the manufacture and being viewed as a disadvantage.
EP 0 171 754 A1 also discloses a hot-blast slide valve. This reference discloses of a hot-blast slide valve, particularly for hot-blast systems of blast furnaces, that is composed of a valve housing formed of sheet metal plates, of a valve plate, or a valve hood secured on the valve housing that serves the purpose of accepting the valve plate in the opened condition of the valve, of seats between which the slide plate is situated in the closed condition, of cooling channels and of refractory protective linings toward the hot-blast side, whereby the seat against which the valve plate is supported in the closed condition is composed of metal which is in thermal contact with a coolant, and whereby the side opposite the said seat is only composed of refractory material.
The hot-blast slide valve disclosed, consequently, comprises cooling channels only toward the hot-blast side, this being considered disadvantageous with respect to the cooling effect under high load. The structure at the hot-blast entry side is as complicated and involved to manufacture as the housings set forth above.
Finally, German Published Application 25 38 357 discloses a high-temperature slide valve, particularly a hot-blast slide valve, comprising a water-cooled valve housing that is provided with two end flanges, this valve housing comprising coolant channels and, in particular, water-cooled sealing ledges as well as a chamber arranged transversely relative to the longitudinal axis of the flow-through cross-section of the gas passage, a valve plate for closing and opening this flow cross-section being guided in said chamber, whereby an actuation means is detachably secured to the housing at one end of this chamber, whereby the entire middle part of the valve housing that surrounds the chamber for the valve plate is rectangularly fashioned on all sides and has the end face lying opposite the mounting side for the actuation means provided with a terminating wall.
It is provided in one development that coolant channels which attach outside of the middle part and circulating around the tubular projections of the valve housing are provided in addition to coolant channels within the sealing ledges, whereby the coolant that initially flows through the sealing ledges is connected to the coolant discharge.
Even though it is considered an advantage that the valve housing can be implemented as a simple weldment, it nonetheless remains as a disadvantage that the component parts employed for that purpose (for example, the coolant channels) must, at least partly, be specifically manufactured for this purpose with considerable outlay.